Earth's Layers

Front

What are the four main layers of the Earth.

Back

The four main layers of the Earth are the crust, mantle, outer core, and inner core.

Front

1. What are the lithosphere and
   asthenosphere?  How are they related?

Back

Lithosphere is the hard outer layer of the
Earth that floats on top of the softer,
hotter Asthenosphere

Front

Describe the outer core and inner core of the Earth.

Back

Outer Core - Liquid Metal
Inner Core - Solid Metal (but hotter!)

Front

1. Why is the inner core solid, despite its high temperature?

Back

INTENSE PRESSURE (14,000 miles of stuff pushing down on it)

Front

1. What is the Theory of Plate Tectonics?  What is a plate?
   

Back

Theory that all of the Earth’s crust is broken into pieces. Those pieces are called plates.

Front

1. How do the plates move?

Back

Mantle material heats up near the core, rises, and then cools off near the crust, causing it to sink and cycle pushing and pulling on the crust causing it to move.

Front

1. What is the Theory of Continental Drift?

Back

Theory that the continents have shifted from one place to another over time.

Front

Describe Pangaea.

Back

Super continent with all of the continents connected back 250+ million years ago

Front

1. There are several pieces of evidence for continental drift.  Describe them:

Back

• Coastal evidence: Coast lines match across oceans

• Fossil evidence: Same dead stuff found on different continents that could not travel over the ocean/distances

Mountain evidence: Mountain ranges match across oceans.

Front

1. About how fast are the continents moving?

Back

1.5 cm per year